Subglottic stenosis (SGS) and tracheal stenosis (TS) are rare conditions that can cause significant breathing difficulties and, if not properly managed, may lead to life-threatening complications. Despite their clinical importance, debate continues regarding the optimal management of adult SGS and TS, and no comprehensive guidelines have been established to date. The Korean Bronchoesophagological Society appointed a task force to develop clinical practice guidelines with the goal of providing evidence-based recommendations for managing SGS and TS in adults. The task force conducted a systematic review of the relevant literature by searching PubMed, Embase, and the Cochrane Library using predefined search terms aligned with key clinical questions. The quality of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach, which also informed the formulation and reporting of the recommendations. The strength of each recommendation reflects the guideline panel’s confidence that the benefits of an intervention outweigh its risks for eligible patients. After drafting the guidelines, feedback was obtained through Delphi questionnaires completed by members of the Korean Bronchoesophagological Society. Ultimately, the committee developed 17 evidence-based recommendations across four categories: initial evaluation, medical management, surgical treatment, and postoperative management and rehabilitation. These guidelines aim to support clinicians in delivering optimal care to adult patients with SGS and TS.

Background: This study aims to compare the effects of short- and intermediate-acting erythropoiesis-stimulating agents (ESAs) on hemoglobin (Hb) variability in patients undergoing maintenance hemodialysis. Methods: This retrospective cohort study included 119 patients who were classified into two groups based on ESA type: short-acting ESA (epoetin alfa/beta [EPO], n=48) and intermediate-acting ESA (darbepoetin alfa [DPO], n=71). Hb levels were measured 11 times at 4-week intervals from ESA therapy initiation to 40 weeks of follow-up. This study used established metrics from previous research, including standard deviation (SD), coefficient of variation (CV), and residual SD, to quantify Hb variability. Results: Over the 40-week study period with 4-week measurement intervals, mean Hb levels were comparable between the two ESA groups. In the EPO and DPO groups, SD was 0.67±0.19 g/dL and 0.69±0.22 g/dL, respectively (p=0.516), CV was 0.06±0.02 and 0.07±0.02, respectively (p=0.480), and residual SD was 0.73±0.21 g/dL and 0.76±0.26 g/dL, respectively (p=0.463). No significant differences in Hb variability were observed between the groups over 40 weeks using SD, CV, and residual SD. Conclusion This retrospective cohort study showed comparable mean Hb levels and Hb variability indices between groups. With respect to Hb variability, the findings reveal no clear basis for prioritizing either short-acting or intermediate-acting ESA.

Primary antibody deficiency (PAD) is the most common form of primary immunodeficiency (PID) in adults, although the overall prevalence remains low. Recent studies have suggested a rising incidence due to changes in environmental factors and increased awareness. PID typically presents with recurrent upper and lower respiratory tract infections but may also be associated with allergic and autoimmune diseases, resulting in various clinical manifestations. This report presents three representative adult cases of PAD— X-linked agammaglobulinemia (XLA), common variable immunodeficiency (CVID), and IgG3 subclass deficiency (IgG3D) with bronchial asthma—offering insights into their diagnosis and long-term management. These cases emphasize the need to suspect XLA in patients with recurrent pneumonia and bronchiectasis, to recognize chronic severe urticaria as a potential clinical clue for CVID, and to evaluate IgG3D in asthma patients with frequent viral infections despite standard care. Through these examples, this clinical insight underscores the importance of early suspicion of PID, comprehensive immunological evaluation and individualized treatment strategies in improving outcomes for adult PID patients.

Background: While enteral feeding intolerance (EFI) is associated with worse clinical outcomes in critically ill patients, the relationship between the number of days of EFI and mortality outcomes remains unclear. Methods: We retrospectively analyzed adult patients admitted to the medical intensive care unit (ICU) with septic shock at a tertiary referral center. EFI was defined as the presence of vomiting, abdominal distension, pain, diarrhea, or radiographic evidence of ileus. EFI status was assessed daily, and we evaluated the prognostic impact of total number of EFI days during the first 3 days of enteral feeding on clinical outcomes. Results: A total of 94 patients were included in the analysis, with 77 (81.9%) experiencing EFI. During the first 3 days of enteral feeding, 25 patients (26.6%) experienced EFI for 1 day, 22 patients (23.4%) experienced EFI for 2 days, and 30 patients (31.9%) experienced EFI for all 3 days. The total number of EFI days was identified as an independent risk factor of 90-day mortality (adjusted hazard ratio, 1.400; 95% CI 1.021–1.919). Higher total EFI days was significantly associated with increased ICU mortality (P for trend=0.036), in-hospital mortality (P for trend=0.007), 30-day mortality (P for trend=0.004), and 90-day mortality (P for trend=0.006). Conclusions An increase in the total number of EFI days was significantly associated with mortality outcomes in patients with septic shock, suggesting that EFI may serve as a useful indicator for predicting outcomes in this population.

Background/Aims: The kidneys and retina are highly vascularized organs that frequently exhibit shared pathologies, with nephropathy often associated with retinopathy. Previous studies have successfully predicted estimated glomerular filtration rates (eGFRs) using fundus photographs. We evaluated the performance of the Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formulas in eGFR prediction. Methods: We enrolled patients with fundus photographs and corresponding creatinine measurements taken on the same date. One photograph per eye was randomly selected, resulting in a final dataset of 45,108 patients (88,260 photographs). Data including sex, age, and blood creatinine levels were collected for eGFR calculation using the MDRD and CKD-EPI formulas. EfficientNet B3 models were used to predict each parameter. Results: Deep neural network models accurately predicted age and sex using fundus photographs. Sex was identified as a confounding variable in creatinine prediction. The MDRD formula was more susceptible to this confounding effect than the CKD-EPI formula. Notably, the CKD-EPI formula demonstrated superior performance compared to the MDRD formula (area under the curve 0.864 vs. 0.802). Conclusions Fundus photographs are a valuable tool for screening renal function using deep neural network models, demonstrating the role of noninvasive imaging in medical diagnostics. However, these models are susceptible to the influence of sex, a potential confounding factor. The CKD-EPI formula, less susceptible to sex bias, is recommended to obtain more reliable results.

Solid pseudopapillary neoplasms (SPNs) are uncommon pancreatic tumors that primarily affect young females. We report a case of a 24-year-old female diagnosed with SPN and liver metastasis during a routine examination. Imaging revealed an 8-cm pancreatic mass with multiple liver metastases. Histopathology confirmed SPN. Subsequent next-generation sequencing revealed a CTNNB1 mutation.The patient underwent a total pancreatectomy with splenectomy, right hemihepatectomy, and intraoperative radiofrequency ablation.Two years after the surgery, she remained complication-free. She is under regular surveillance. This case underscores the importance of early detection and comprehensive management of SPN.

Solid pseudopapillary neoplasms (SPNs) are uncommon pancreatic tumors that primarily affect young females. We report a case of a 24-year-old female diagnosed with SPN and liver metastasis during a routine examination. Imaging revealed an 8-cm pancreatic mass with multiple liver metastases. Histopathology confirmed SPN. Subsequent next-generation sequencing revealed a CTNNB1 mutation.The patient underwent a total pancreatectomy with splenectomy, right hemihepatectomy, and intraoperative radiofrequency ablation.Two years after the surgery, she remained complication-free. She is under regular surveillance. This case underscores the importance of early detection and comprehensive management of SPN.

Purpose: The Korean Cancer Study Group (KCSG) is a nationwide cancer clinical trial group dedicated to advancing investigator-initiated trials (IITs) by conducting and supporting clinical trials. This study aims to review IITs conducted by KCSG and quantitatively evaluate the survival and financial benefits of IITs for patients. Materials and Methods: We reviewed IITs conducted by KCSG from 1998 to 2023, analyzing progression-free survival (PFS) and overall survival (OS) gains for participants. PFS and OS benefits were calculated as the difference in median survival times between the intervention and control groups, multiplied by the number of patients in the intervention group. Financial benefits were assessed based on the cost of investigational products provided. Results: From 1998 to 2023, KCSG conducted 310 IITs, with 133 completed and published. Of these, 21 were included in the survival analysis. The analysis revealed that 1,951 patients in the intervention groups gained a total of 2,558.4 months (213.2 years) of PFS and 2,501.6 months (208.5 years) of OS, with median gains of 1.31 months in PFS and 1.58 months in OS per patient. When analyzing only statistically significant results, PFS and OS gain per patients was 1.69 months and 3.02 months, respectively. Investigational drug cost analysis from six available IITs indicated that investigational products provided to 252 patients were valued at 10,400,077,294 won (approximately 8,046,481 US dollars), averaging about 41,270,148 won (approximately 31,930 US dollars) per patient. Conclusion Our findings, based on analysis of published research, suggest that IITs conducted by KCSG led to survival benefits for participants and, in some studies, may have provided financial benefits by providing investment drugs.